Statistics indicate that three quarters of American homes have at least one smoke detector. However, the National Fire Protection Agency estimates that ⅓ of those detectors do not work, often because of dead or missing batteries. The industry is aware of the problems associated with smoke detectors and has responded with several safety features that are effective, but no flawless as evidence in the above statistics. Modern smoke detectors warn a person when a smoke detectors battery is low by producing a chirping sound, one a minute. This chirp continues for approximately a month when the battery goes dead or until someone either replaces or removes the battery. Often users will remove the battery in order to silence the disruptive chirping rather than replace it with a new battery.
Dead batteries probably reflect the lack of regular testing and maintenance and the problem may be compounded by some individuals unfamiliarity with the meaning of the sounds and signals now used to indicate low battery power.
A prevalent smoke detector on the market today includes a hinged cover that is attached to the detectors base plate in which the base plate houses the battery and the electrical components. The hinge cover is designed to that it cannot be closed unless the battery is present. However, the hinged cover can easily be forced into position when no battery is present. Furthermore, when the hinge cover is not in the closed position, there is no visual warning indicating a missing battery, just exposed electronic circuitry. Again a person may assume that the detector to falter and remove it completely.
Another smoke detector designed includes a battery drawer that slides in and out from the smoke detector on a horizontal motion. The compartment door cannot be repositioned into the smoke detector unless the battery is present. The door however is slightly bigger than the battery and therefore offers no effective visual warning that the battery is missing.
Furthermore, if the smoke detectors battery has been repositioned so that the batteries terminals are reversed or are not in contact with the battery, the hinged covered battery compartment may still be able to be closed, since the battery is actually present. In the case of the external battery compartment, the detector can still be mounted since the battery is in the compartment.
Furthermore, landlords are responsible for defective and/or non-operative smoke detectors which are located inside residential apartment units. There is no way for a landlord to assure or prove that he has placed a fresh battery inside the smoke detector and/or be able to conclusively give evidence that the tenant has not removed and/or otherwise tampered with the detector.
Therefore, there is a need for a tamper indicator for smoke detectors which would allow a landlord of apartment buildings and/or official of the Fire Department to be able to determine that in fact a battery has been installed on a certain date and has not been tampered with since.